niacin
From Longman Dictionary of Contemporary EnglishRelated topics: Human, Drugs, medicinesniacinni‧a‧cin /ˈnaɪəsɪn/ noun [uncountable] a type of vitamin that is good for your skin and your nervous systemExamples from the Corpusniacin• Untreated maize is reluctant to give up its B vitamins, particularly its niacin.Origin niacin (1900-2000) nicotine + acid + -in chemical compound